Multi-component elastic seismic data collected at large offsets have the potential to be used in seismic imaging and velocity analysis. In this study, we present an approach for converted-phase elastic-transmission migration ...

A commonly used model for a transversely anisotropic crack rock is that by Hudson
(1980, 1981). This model is based on a simplified analysis of a thin circular crack, with
displacement and stress conditions specified on ...

A seismic wave propagating in a fluid-saturated porous media, moves ions in the double layer between the fluid and solid and induces an electric field. When there is discontinuity (such as a fracture), the seismic wave ...

The goal of time-lapse imaging is to identify and characterize regions in which the
earth's material properties have changed between surveys. This requires an effective deployment of sources and receivers to monitor the ...

For linear wave propagation in anisotropic media, the principle of superposition still
holds. The decomposition of the acoustic dipole log is based on this principle. In the
forward decomposition inline and crossline ...

The Qualibou Caldera has been studied since the 1970’s for possible development of
geothermal power generation. In 1974 dipole-dipole resistivity measurements were
performed in the area. The apparent resistivity data was ...

In many applications, sequestering CO[subscript 2] underground for example,
determining whether or not the medium has changed is
of primary importance, with secondary goals of locating and
quantifying that change. We ...

Field testing has been conducted to evaluate a model which predicts the
permeability and orientation of a permeable zone, in a deep water well in crystalline
rock. Tube waves are generated by seismic P-waves incident on ...

Azimuthally-dependent P-wave AVO (amplitude variation with offset) responses can
be related to open fracture orientation and have been suggested as a geophysical tool
to identify fracture orientation in fractured oil and ...

In Vertical Seismic Profiling surveys tube waves are generated by compressional waves impinging on subsurface fractures or permeable zones. The problem of generation of these waves by a non-normal incident P wave for an ...

In Vertical Seismic Profiling tube waves are generated by compressional
waves impinging on subsurface fractures or permeable zones. The amplitude of
tube waves is dependent upon the formation permeability, the length of ...

Wave propagation in bonded and unbonded cased boreholes is examined through the calculation cif synthetic full waveform acoustic logs. The models consist of a central fluid borehole surrounded by a number of fluid and solid ...

Ground penetrating radar (GPR) signatures, such as reflection moveout, are sensitive to the presence of azimuthal anisotropy. Azimuthal anisotropy can occur as an intrinsic property of the medium and/or due to the presence ...

Direct determination of formation shear wave travel time is impossible in "slow" formations where the shear wave velocity is lower than the borehole fluid (mud) velocity. However, the Stoneley waves in these formations are ...

In boreholes where formation shear velocity is lower than borehole fluid velocity neither refracted shear waves nor pseudo-Rayleigh waves can propagate. When frequency response of the sonde does not extend to low frequencies ...

Open fractures are of interest in many areas such as ground water contamination, hazardous waste disposal, oil and gas recovery, and geothermal energy extraction. In
borehole geophysics and engineering, fractures are ...

NMR methods are widely used to probe the structure and fluid dynamics of porous materials including such diverse materials as cheese and chocolate, cosmetics and pharmaceuticals, solvents in resins and soft matter, biological ...

In this paper, we demonstrate that dispersion analysis of cross-dipole data has promising
potential not only for differentiating stress-induced anisotropy from intrinsic anisotropy, but also for providing information on ...

In this paper we first present a technique for measuring dispersion curves from array data, that is both simple and efficient. We demonstrate its performance on both synthetic and field data. We then use the technique to ...